US5851330A - Method of insulating a pipe with a tubular sheathing - Google Patents

Method of insulating a pipe with a tubular sheathing Download PDF

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Publication number
US5851330A
US5851330A US08/952,277 US95227797A US5851330A US 5851330 A US5851330 A US 5851330A US 95227797 A US95227797 A US 95227797A US 5851330 A US5851330 A US 5851330A
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US
United States
Prior art keywords
tubular
pipe
tubular member
sheathing
discs
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US08/952,277
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English (en)
Inventor
Ian Cridland
Jens Husbjerg
Finn rtoft
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rockwool AS
Original Assignee
Rockwool International AS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=8095234&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US5851330(A) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Rockwool International AS filed Critical Rockwool International AS
Application granted granted Critical
Publication of US5851330A publication Critical patent/US5851330A/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/02—Shape or form of insulating materials, with or without coverings integral with the insulating materials
    • F16L59/021—Shape or form of insulating materials, with or without coverings integral with the insulating materials comprising a single piece or sleeve, e.g. split sleeve, two half sleeves
    • F16L59/022—Shape or form of insulating materials, with or without coverings integral with the insulating materials comprising a single piece or sleeve, e.g. split sleeve, two half sleeves with a single slit
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/14—Arrangements for the insulation of pipes or pipe systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/14—Arrangements for the insulation of pipes or pipe systems
    • F16L59/16—Arrangements specially adapted to local requirements at flanges, junctions, valves or the like
    • F16L59/22—Arrangements specially adapted to local requirements at flanges, junctions, valves or the like adapted for bends
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y10T156/1002—Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina
    • Y10T156/1028—Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina by bending, drawing or stretch forming sheet to assume shape of configured lamina while in contact therewith
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y10T156/1052—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
    • Y10T156/1062—Prior to assembly

Definitions

  • the present invention relates to a method of insulating a pipe wherein a tubular sheathing comprising an optionally radially slitted, tubular member of bonded mineral fibres oriented essentially in planes perpendicular to the longitudinal axis of the tubular member, and a sheet material, which by gluing is attached to the outer side of the tubular member, is mounted so as to envelop the pipe.
  • DK 157 627 B and 159 941 B disclose tubular sheathings of the above kind where the sheet material e.g. consists of a paper layer or a plastics or metal foil.
  • the glue is applied in the form of essentially parallel, narrow stripes or rows of glue points, which stripes or rows extend substantially perpendicularly to the longitudinal axis of the tubular member.
  • the tubular member of mineral wool may be composed of a coaxial assembly of slitted insulation discs having a central hole.
  • the assembly of discs is thus provided by sawing out from a stack of bonded mineral fiber sheets, whereafter the assembly thus obtained is enveloped in a sheet material e.g. of a corrugated metal foil.
  • the instant tubular sheathings are used for heat insulation of pipes for transport of hot or cold media, and in view of the handling as well as the mounting of the tubular sheathings on straight pipes it is important that they possess a certain rigidity.
  • Pipes of the above kind normally also comprise bends, e.g. 90° bends, and in order to be able to insulate such bends effectively it is important that the tubular sheathings are bendable without formation of sharp elbows.
  • the method according to the invention is characterized in that the tubular sheathing, prior to being mounted on the pipe, is alternatingly compressed and stretched in axial direction in a zone in which the tubular sheathing is to insulate a bend on the pipe.
  • the invention is based on the discovery that such treatment of a tubular sheathing of the kind stated in the premable entails that the bonds between the mineral fibres and/or the bonds between the outer side of the tubular sheathing and the sheet material in the zone in question are changed in such a way that the tubular sheathing at the particular site becomes easily bendable, but otherwise retains its rigidity across the remaining portion of the length of the tubular sheathing.
  • the tubular sheathing used being oriented in planes perpendicular to the longitudinal axis of the tubular sheathing, the tubular sheathing possesses high resistance in radial direction, and even after having been treated in the way described the tubular sheathing continues to possess considerable resistance to such deformation in the particular area, and consequently satisfactory insulation of the pipe in the bend-area is still obtainable.
  • the invention thus offers the advantage that use can be made of tubular sheathings which, by appropriate selection of density for the tubular mineral fiber member, amount and kind of binder for bonding the mineral fibres and sheet material, have a desired rigidity with respect to handling, and concomitantly that when insulating bends such bendability is obtainable that a good insulation on bends on the pipe is easily obtainable.
  • the tubular sheathings used in the method according to the invention are preferably composed of an assembly of annular, axially slitted discs, a particularly large bendability hereby being obtained following a treatment as described.
  • the preparation of such tubular sheathings may be performed by providing a stack of sheets of mineral fibres essentially being oriented in planes parallel to the sheet sides, and by simultaneously cutting out a number of annular discs corresponding to the number of mineral fiber sheets by means of a band or string shaped saw in a direction of movement which is essentially perpendicular to the main surfaces of the mineral fiber sheets.
  • the tubular member expediently consists of loosely abutting discs, but, if desired, they may also be glued together so as to constitute a coherent element.
  • the mineral fiber sheets used for providing the annular discs or the tubular member are preferably sheets prepared by subjecting a mineral fiber web obtained by pendulum folding to a longitudinal and a vertical compression where the longitudinal compression ratio is preferably from 2:1 to 10:1, discs/a tubular member hereby being obtained having an optimum combination of strength and insulation capacity.
  • the assembly or the tubular member Prior to gluing the sheet material onto the outer side of the assembly of annular discs or the tubular member, the assembly or the tubular member is compressed, preferably in the longitudinal direction, to such an extent that the length is reduced by as much as 20%.
  • the central hole in the insulation discs may be circular and have a diameter adapted to the outer diameter of a pipe to be insulated. However, it may be expedient to shape the hole in such a way that the tubular sheathing constituted by the insulation discs can be used for insulating pipes having different diameters, e.g. for insulating pipes having diameters varying between 21 mm and 27 mm.
  • radially inwardly directed protrusions having such flexibility as to be adaptable to pipes having different diameters, at the same time, however, ensuring that the aggregate tubular sheathing is fixed in relation to the pipe which it is to insulate.
  • the assembly is preferably enveloped in sheet material while being mounted on a common mandrel, in order thereby to maintain correct orientation of the discs and ease the handling of the number of discs which are to constitute a finished tubular sheathing.
  • the rings provided by the cutting out may be pushed out of the stack as a unit and mounted coaxially in order subsequently to be enveloped in a sheet material, such as an aluminum foil, it is also possible to juxtapose several sets of cut out rings in succession so as to provide tubular sheathings of desired lengths, even up to very considerable lengths.
  • the sheet material is preferably a foil, e.g. a metal foil, such as an aluminum foil, having a thickness of 15-35 ⁇ m, e.g. 20 ⁇ m.
  • a particularly good strength is obtained by using a reinforced aluminum foil.
  • the sheet material is a foil, it is advantageously attached to the outer side of the assembly of insulation discs by means of a binder, preferably a thermoplastic binder, e.g. comprising polyethylene.
  • the affixation of the foil may in that case be effected by using a foil coated with a binder, and undertaking heating of the foil in connection with the application thereof on the assembly of insulation discs.
  • a particularly good adhesion of the foil is achieved by mechanically pressing the heated foil against the outer side of the assembly of insulation discs.
  • the binder is pressed into the fibrous insulation material. It is particularly advantageous to use a binder which is adhesive at room temperature.
  • an inorganic binder such as a silicate binder.
  • a metal foil paper may be used.
  • the sheet material is not necessarily attached to the discs by full adhesion, since it may suffice to glue it on in longitudinally extending stripes. A particularly good result is achieved with longitudinally extending wide stripes of a thermoplastic binder covering about 80% of the outer side of the tubular member.
  • the sheet material is smooth, but may be corrugated with alternating protrusions and recesses extending perpendicularly to the longitudinal axis of the tubular sheathing.
  • FIG. 1 is a perspective view of a tubular sheathing for use in the method according to the invention with a partly released sheet material
  • FIGS. 2-3 are sectional views of annular mineral fiber discs having different hole shapes.
  • FIG. 1 shows a tubular sheathing composed of an assembly of annular insulation discs 1 consisting of mineral fibres, the assembly on one side having a first throughgoing cutting zone 2, and on the other side a second non-throughgoing cutting zone 3, the latter serving to facilitate the opening of the tubular sheathing when it is to be fitted on a pipe.
  • the assembly of insulation discs is enveloped in a sheet material 4 e.g. of aluminum foil which is glued onto the outer side of the assembly by means of an adhesive not shown.
  • the portion of the sheet material 4 stretching along the throughgoing cutting zone 2 has an extension 5 which serves as overlapping zone after the mounting of the tubular sheathing on a pipe which it is desired to insulate and which is e.g. provided with a selfadhesive glue stripe.
  • FIG. 2 and FIG. 3 show annular insulation discs 20 21 respectively having axially extending cutting zones 22.
  • the inner side of the insulation discs is provided with radially inwardly directed resilient protrusions 23 so as to be usable for insulating pipes having different outer diameters.
  • the cut out cores may optionally be used for cutting out further tubular sheathings having an outer diameter corresponding to the outer diameter of the cores. In that case any radial protrusions on the outer side of the core pieces must be removed.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Insulation (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Insulating Bodies (AREA)
  • Pipeline Systems (AREA)
  • Insulators (AREA)
  • Packaging Of Annular Or Rod-Shaped Articles, Wearing Apparel, Cassettes, Or The Like (AREA)
US08/952,277 1995-05-22 1996-05-22 Method of insulating a pipe with a tubular sheathing Expired - Fee Related US5851330A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DK58595 1995-05-22
DK0585/95 1995-05-22
PCT/DK1996/000222 WO1996037728A1 (en) 1995-05-22 1996-05-22 A method of insulating a pipe with a tubular sheathing

Publications (1)

Publication Number Publication Date
US5851330A true US5851330A (en) 1998-12-22

Family

ID=8095234

Family Applications (1)

Application Number Title Priority Date Filing Date
US08/952,277 Expired - Fee Related US5851330A (en) 1995-05-22 1996-05-22 Method of insulating a pipe with a tubular sheathing

Country Status (16)

Country Link
US (1) US5851330A (hu)
EP (1) EP0828965B1 (hu)
AT (1) ATE199976T1 (hu)
AU (1) AU5892896A (hu)
BG (1) BG62948B1 (hu)
CZ (1) CZ293862B6 (hu)
DE (1) DE69612196T2 (hu)
DK (1) DK0828965T3 (hu)
ES (1) ES2155189T3 (hu)
HU (1) HU221031B1 (hu)
NO (1) NO314468B1 (hu)
PL (1) PL179755B1 (hu)
RU (1) RU2162563C2 (hu)
SK (1) SK283011B6 (hu)
UA (1) UA44775C2 (hu)
WO (1) WO1996037728A1 (hu)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090320392A1 (en) * 2006-07-25 2009-12-31 Deutsche Rockwool Mineralwoll Gmbh & Co. Ohg Wall leadthrough for leading a line through a building wall
US7913718B1 (en) 2008-01-10 2011-03-29 Cornwall Kenneth R Noise reduction system
US20110309207A1 (en) * 2009-02-09 2011-12-22 Lisega Aktiengesellschaft Cold-insulated pipe support and installation
US20120124928A1 (en) * 2010-11-19 2012-05-24 Spider Plug, LLC Fire Stop and Method of Use Thereof
US9482381B1 (en) 2015-12-18 2016-11-01 Paroc Group Oy Mineral wool pipe insulation

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9717484D0 (en) 1997-08-18 1997-10-22 Rockwool Int Roof and wall cladding
FR2806149B1 (fr) 2000-03-08 2002-05-03 Saint Gobain Isover Procede et dispositif d'isolation d'elements tubulaires
CN100523584C (zh) * 2001-07-17 2009-08-05 圣戈班伊索福公司 包含有毡制品的组合件及其制造方法
FR2831645B1 (fr) * 2001-10-31 2004-04-02 Saint Gobain Isover Coquille de calorifugeage compressee
WO2003008159A1 (en) 2001-07-17 2003-01-30 Saint-Gobain Isover A/S A method and an apparatus for producing elements by punching
SE527024E (sv) 2004-04-23 2014-09-30 Saint Gobain Isover Ab Ytbeklädnadsmaterial i laminatform samt isoleringssystem innefattande ett dylikt ytbeklädnadsmaterial
DE102004062601A1 (de) * 2004-12-24 2006-07-06 Saint-Gobain Isover G+H Ag Dämmelement für Doppel-oder Mehrfachleitungen
FI20096309A (fi) * 2009-12-11 2011-06-12 Paroc Oy Ab Putkieristyskourun suljinmekanismi ja sen valmistusmenetelmä
DE102013019682A1 (de) * 2013-11-22 2015-05-28 Saint-Gobain Isover G+H Ag Dämmelement zur Wärme- und/ oder Schalldämmung von Rohren, insbesondere Kaminrohren
RU173453U1 (ru) * 2016-10-31 2017-08-28 Общество с ограниченной ответственностью "Изомин" Теплоизоляционное изделие для труб
RU172971U1 (ru) * 2017-02-10 2017-08-02 Общество с ограниченной ответственностью "ПРОМТЕХИНЖИНИРИНГ" Сегмент теплоизоляционный с покрытием
EP3623684B1 (de) * 2018-09-13 2021-04-07 Geberit International AG System umfassend eine rohrisolierung und ein rohr mit klemmfitting
FR3099225B1 (fr) * 2019-07-25 2021-12-24 Saint Gobain Isover Structure isolante pour conduite de fluide
RU2758400C2 (ru) * 2020-03-02 2021-10-28 Евгений Евгеньевич Мясников Обжимное устройство для теплоизоляции трубопровода
CN115698576A (zh) 2020-07-22 2023-02-03 洛科威有限公司 隔热管道系统、隔热管段和用于制造隔热管段方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4205105A (en) * 1977-01-21 1980-05-27 P. H. Thermal Products Limited Pipe insulation
US4428991A (en) * 1978-03-15 1984-01-31 Superfos Glasuld A/S Plate-shaped insulation member and a method for manufacturing such a member
US4743329A (en) * 1985-02-22 1988-05-10 Sumitomo Electric Industries, Ltd. Process for manufacturing of composite pipes
US5024249A (en) * 1989-05-17 1991-06-18 Carol Botsolas Specialized one-piece pipefitting cover for insulated strainer and lateral 45 degree -Y
US5056564A (en) * 1988-02-19 1991-10-15 Isover Saint-Gobain Insulating mat for bodies of which at least portions of the surface are curved, and in particular for pipes, and the use of such a mat

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE373928B (hu) * 1972-12-11 1975-02-17 Rockwool Ab
DK159941C (da) * 1987-11-06 1993-02-22 Rockwool Int Element til isolering af isaer krumme roer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4205105A (en) * 1977-01-21 1980-05-27 P. H. Thermal Products Limited Pipe insulation
US4428991A (en) * 1978-03-15 1984-01-31 Superfos Glasuld A/S Plate-shaped insulation member and a method for manufacturing such a member
US4743329A (en) * 1985-02-22 1988-05-10 Sumitomo Electric Industries, Ltd. Process for manufacturing of composite pipes
US5056564A (en) * 1988-02-19 1991-10-15 Isover Saint-Gobain Insulating mat for bodies of which at least portions of the surface are curved, and in particular for pipes, and the use of such a mat
US5024249A (en) * 1989-05-17 1991-06-18 Carol Botsolas Specialized one-piece pipefitting cover for insulated strainer and lateral 45 degree -Y

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090320392A1 (en) * 2006-07-25 2009-12-31 Deutsche Rockwool Mineralwoll Gmbh & Co. Ohg Wall leadthrough for leading a line through a building wall
US8438804B2 (en) * 2006-07-25 2013-05-14 Deutsche Rockwoll Mineralwoll Gmbh & Co. Ohg Wall leadthrough for leading a line through a building wall
US7913718B1 (en) 2008-01-10 2011-03-29 Cornwall Kenneth R Noise reduction system
US20110309207A1 (en) * 2009-02-09 2011-12-22 Lisega Aktiengesellschaft Cold-insulated pipe support and installation
US8763648B2 (en) * 2009-02-09 2014-07-01 Lisega Aktiengesellschaft Cold-insulated pipe support and installation
US20120124928A1 (en) * 2010-11-19 2012-05-24 Spider Plug, LLC Fire Stop and Method of Use Thereof
US9482381B1 (en) 2015-12-18 2016-11-01 Paroc Group Oy Mineral wool pipe insulation

Also Published As

Publication number Publication date
BG62948B1 (bg) 2000-11-30
DK0828965T3 (da) 2001-04-23
DE69612196D1 (de) 2001-04-26
HUP9900319A2 (hu) 1999-05-28
PL323536A1 (en) 1998-03-30
UA44775C2 (uk) 2002-03-15
ES2155189T3 (es) 2001-05-01
NO314468B1 (no) 2003-03-24
NO975370L (no) 1998-01-08
RU2162563C2 (ru) 2001-01-27
BG102057A (en) 1999-01-29
SK157297A3 (en) 1998-10-07
AU5892896A (en) 1996-12-11
SK283011B6 (sk) 2003-02-04
DE69612196T2 (de) 2001-09-06
WO1996037728A1 (en) 1996-11-28
HU221031B1 (hu) 2002-07-29
EP0828965B1 (en) 2001-03-21
CZ360897A3 (cs) 1998-05-13
EP0828965A1 (en) 1998-03-18
HUP9900319A3 (en) 1999-11-29
NO975370D0 (no) 1997-11-21
ATE199976T1 (de) 2001-04-15
PL179755B1 (pl) 2000-10-31
CZ293862B6 (cs) 2004-08-18

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